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SME tax return required documents in Thundorf: the practical guide

Between VAT, social contributions and the year-end close, a Swiss SME juggles dozens of deadlines a year. This page focuses on SME tax return in Thundorf: what the law requires, what can be automated, and when to delegate.

The Swiss legal frame for SME tax return

A small business does not mean small obligations: from the first salary or the first VAT return, mistakes get expensive — in Thundorf as anywhere.

Art. 957a CO requires complete, truthful and systematic recording of transactions, each entry backed by a supporting document. For SME tax return, that means in practice: no movement without a receipt, and an audit trail that can be reconstructed at any time — including during a VAT or AHV inspection.

A Swiss SME's accounting calendar

Extensions exist and can be requested: cantonal deadlines for the tax return, deferral of the VAT filing on a reasoned request. But an extension does not stop interest: on VAT, default interest runs from the ordinary due date even when more time has been granted.

For SME tax return, deadline discipline is worth real money: default interest on late VAT, AHV adjustments, tax fines. A shared deadline calendar — fed by up-to-date figures — remains the simplest safeguard.

Year-end closing: how the mechanics work

Companies exceeding two of three thresholds for two consecutive years — CHF 20 million balance sheet total, CHF 40 million revenue, 250 full-time positions — move to an ordinary audit. Below that, the limited audit applies, and companies with no more than ten full-time positions on annual average can opt out with the consent of all shareholders.

A company in Thundorf that presents clean, punctual annual accounts gains credibility — with its bank, its suppliers and the tax administration.

Team analysing financial charts around a table

Outsource SME tax return or keep it in-house?

Outsourcing SME tax return to a fiduciary frees up time and secures compliance; keeping it in-house preserves a continuous view and costs less in fees. The best answer is often hybrid: the company captures and digitises as it goes, the fiduciary supervises, closes the books and represents the company before the authorities.

A clear mandate agreement states who does what by when: document handover, posting deadlines, filing calendar, and responsibility for delays. A shared platform (same data, same document archive) between the company and its fiduciary eliminates binder ping-pong and duplicate entry.

Thundorf: what changes, what does not

Thundorf (postal code 8512, canton Thurgau) applies the same federal rules as the rest of the country: what changes in Thundorf are the cantonal counterparts — tax administration, compensation office, commercial register.

Thundorf requires no special bookkeeping: the Code of Obligations applies at postal code 8512 as everywhere else, and a well-kept digital file transfers smoothly to any auditor in the canton.

Frequently asked questions

How long must records related to SME tax return be kept?

Ten years from the end of the financial year concerned (art. 958f CO). Electronic retention is permitted if the integrity and readability of the records are guaranteed — a serious digital archive validly replaces paper binders. A business in Thundorf can therefore archive fully digitally.

Can SME tax return be automated with AI?

Largely, yes: automatic document reading, posting suggestions, bank reconciliation via QR references and VAT exports. Human approval remains essential — AI prepares, the professional checks. That is exactly how MyFiducia.ai approaches SME tax return.

When must a business register for VAT?

As soon as its worldwide annual turnover reaches CHF 100,000 (CHF 250,000 for non-profit sports or cultural associations). Below that, voluntary registration remains possible and often makes sense to reclaim input VAT on investments. The threshold is federal: it applies in Thundorf as everywhere in Switzerland.

When is entry in the commercial register mandatory?

A Sàrl and an SA only come into existence with their registration. A sole proprietorship must register from CHF 100,000 of annual revenue; below that, registration stays voluntary but adds credibility and protects the business name. Registration goes through the canton's commercial register office — for Thundorf too.

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Switch to accounting that keeps itself up to date

MyFiducia.ai automates SME tax return for businesses in Thundorf: AI-read documents, posting suggestions, VAT and exports ready for your fiduciary. Try the platform or browse our other guides.

The application is operated in French.